MicrogravityBRAHMSNCT07499167
BRAHMS: Bed Rest And HypoMetabolism Study
A study testing head down bedrest and caloric restriction in people with Microgravity and Caloric Restriction, run by Centre National d'Etudes Spatiales at 1 site in France.
Trial summary
The goal of this single arm, interventional monocentric clinical trial is to investigate the physiological effects of a combination of head-down bedrest and caloric restriction on the human body. Read more about this study
- Who is it for?
- Ages 20 to 40 years, men onlyHealthy volunteers can take part
- Conditions the study is for
- Microgravity, Caloric Restriction
- What is being tested?
- head down bedrest and caloric restriction
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 10 participants
- Where
- 1 siteFrance
- Study dates
- 10 Mar 2026to 28 Sep 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 20 to 40 years
- Men only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Healthy male volunteers (see below the description of medical tests and laboratory analysis performed at the selection visit)
- Certified as healthy by a comprehensive clinical assessment (detailed medical history and complete physical examination): in particular, free from any known chronic disease or any acute mood or eating disorder, infectious disease or cardiovascular, metabolic, neurological, ENT (especially orthostatic hypotension and vestibular disorders), orthopedic or musculoskeletal disorders.
- 20 to 40 years old
- 165 to 185 cm
- Body Mass Index between 20 and 26 kg.m-2
- Stable body weight in the past 3 months (less than 4% change)
Show all 15Show fewer
- Fat Mass Index (FMI), defined as (bodyfat weigh in kg)/(height in m)2: between 3 and 6 kg.m-2, measured by whole-body DEXA
- Triglyceride level under 1.7 mmol.L-1
- Normal bone mass density at left hip and lumbar spine: T-score>-1.5, measured by DEXA
- VO2peak/VO2max between 35 and 55 mL.min-1.kg-1
- Non-smokers
- No alcohol or drug dependence, no medical treatment on a regular basis
- Affiliated to a Social Security system and, for non-French resident, holding a European Health Insurance Card (EHIC) or a Global Health Insurance Card (GHIC).
- Free of any engagement during the study
- Who agreed to take part in the study and signed the informed consent
Who cannot join
- Any history or presence of clinically relevant chronic disease; any acute infectious disease. Particularly (but not limited to):
- Symptomatic orthostatic hypotension whatever the decrease in blood pressure, or asymptomatic postural hypotension defined by a decrease in SBP equal to or greater than 20 mmHg within 3 minutes when changing from the supine to the standing position
- Personal or family history of thrombosis, genetic mutation for factor V or prothrombin gene
- Cardiac arrhythmia
- Hypertension
- Auto-immune diseases or Raynaud's syndrome
Show all 41Show fewer
- History or symptoms of sleep apnea
- Chronic back pains,
- Vertebral fracture, scoliosis, or herniated disc,
- Color-blindness,
- Self-reported hearing problems or binocular visual acuity under 6/10 after correction
- Vestibular disorders
- Drug addiction
- History of migraines,
- History of hiatus hernia or gastro-esophageal reflux,
- History of thyroid dysfunction or diabetes
- History of head trauma,
- History of neurological diseases (e.g. epilepsy)
- History of genetic muscle and bone diseases of any kind
- Significant history of allergies
- Significant abnormality in blood tests
- Positive serology for hepatitis A, hepatitis B, hepatitis C or AIDS (HIV) virus
- Mood and Eating disorder (current or past), screened with the Hospital Anxiety Depression Scale (HADS), SCOFF (Sick, Control, One, Fat, Food) and the Eating Disorder Examination Questionnaire (EDE-Q)
- Antibiotics exposure 2 months prior to the study
- Major lifestyle changes (e.g. significant weight/body changes, diet or exercises regimen) 6 months prior to the study
- Specific diet (e.g vegan, carnivore, intermittent fasting, dietary supplements consumption)
- History of hypocaloric diet, judged as significant by the investigator
- Subject who, in the judgment of the investigator, is likely to be non-compliant during the study, or unable to cooperate because of a language problem or poor mental development,
- Subject in the exclusion period of another clinical research,
- Subject who received 6000 Euros or more within 12 months for being a research subject,
- Poor tolerance to blood sampling,
- Subject who cannot be contacted in case of emergency,
- Contraindications for MRI: claustrophobia, presence of osteosynthesis material or metal implants,
- Blood donation of more than 7 ml/kg in the 8 weeks prior to the start of the study,
- Vulnerable people according to law "Code de la Santé Publique" (L1121-5 to L1121-8):
- Pregnant or nursing women (urine pregnancy test for women of childbearing potential)
- People deprived of their liberty by an administrative or judicial decision
- People under involuntary psychiatric care
- People admitted in a health or social establishment for purposes other than research
- Minors
- Adults subject to legal protection (subject under guardianship or trusteeship) or unable to express their consent
Trial locations and contacts
1 site in 1 country.
About this study
Official title: BRAHMS: Bed Rest And HypoMetabolism Study Integrative Physiological Responses to 10 Days of Bedrest and Caloric Restriction: An Exploratory Pilot Study In 10 Healthy Men.
The goal of this single arm, interventional monocentric clinical trial is to investigate the physiological effects of a combination of head-down bedrest and caloric restriction on the human body. A set of measurements will assess the changes in the musculoskeletal, cardiovascular, hematological, immune, neurological, cognitive and metabolic systems, in 10 healthy male volunteers.
The main question it aims to answer is: what are the physiological responses to fasting in a microgravity environment?
Read more
In an exploratory study such as this one, where many physiological systems are explored, it is difficult to select a single important endpoint. However, given the known effect of both caloric restriction and head-down bedrest on muscle loss, and its critical importance for the success of space missions, lean body mass, as assessed by DEXA, was chosen as the primary endpoint.
The secondary endpoints are:
- Cardiovascular, muscular, neuro-vestibular and neuropsychological functional performance
- The onset of clinical symptoms and biological changes
Participants will be exposed to a microgravity analog model (head down bed rest) and controled caloric restriction environment for 10 days, multiple physiological assessments will be performed during this period. Followed by a rehab period before leaving the study.
- Conditions
- Microgravity, Caloric Restriction
- Being tested
- head down bedrest and caloric restriction
- Keywords
- Microgravity, Caloric restriction
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
head down bedrest and caloric restrictionOther
the intervention is 10 days of head down bedrest (-6°) and controlled and progressive caloric restriction, then controlled and progressive refeeding
| Study group | Role | What they receive |
|---|---|---|
| Caloric restriction | Experimental | head down bedrest and caloric restriction (250 kcal/day) Receives: Other: head down bedrest and caloric restriction |
What is being measured
The primary outcome is the main question the study is designed to answer.
Lean Body Mass
Lean Body Mass assessed by dual energy x-ray absorptiometry (DEXA)
Measured: At baseline, during the ten days of intervention and until 90 days after the end of the intervention
Secondary outcomes (36)
Change in body fluid compartments by bioelectrical impedance analysis
Extracellular, intracellular and total body water (L) will be estimated by bioimpedance
Measured: At baseline, during the ten days of intervention and until 90 days after the end of the intervention
Change in whole-body Magnetic Resonance Imaging (MRI)
Change in MRI-measured whole-body Lean mass (kg) and Fat mass (kg) will be estimated
Measured: At baseline and at day 9 of intervention period
Change in mood
Change in mood is assessed using the Profile of Mood States (POMS) questionnaire. POMS questionnaire gives 6 measures of mood: Tension/anxiety, Depression, Anger/hostility Dynamism, Fatigue, Confusion A Total Mood Disturbance (TMD) score is calculated by summing the totals for the negative subscales (tension, depression, fatigue, confusion, anger) and then subtracting the totals for the positive subscale (vigor /esteem-related affect).
Measured: At baseline, during the ten days of intervention and until 4 days after the end of the intervention
Assessment of movements by volunteers
Actigraphs attached to wristbands placed on the non-dominant wrist and ankle of each volunteer
Measured: At baseline, during the ten days of the intervention and until 4 days after the end of the intervention
Change in cardiovascular deconditioning and orthostatic tolerance (stand test)
This test continuously measures heart rate (bpm) via a Finapres device while subjects sit for 5 minutes, then stand for 10 minutes and then sit again for 5 minutes
Measured: At baseline and 1 day after the end of intervention period
Changes in orthostatic tolerance
Orthostatic tolerance will be assessed during a tilt test combined with Lower Body Negative Pressure test (LBNP test)
Measured: At baseline and 1 day after the end of intervention period
Changes in peak aerobic power (VO2max test)
Exercise capacity wil be assessed by graded cycling on sitting ergometer until exhaustion
Measured: At baseline and 4 days after the end of intervention period
Changes in plasma volume
Plasma volume (L) will be assessed by the Dill \& Costill method
Measured: At baseline, during the ten days of the intervention and until 4 days after the end of the intervention
Change in long term blood pressure
This test continuously measures Blood Pressure during 24 hours with the SOMNOTouch device.
Measured: At baseline, during the 10 days of the intervention, and 4 days after the end of the intervention
Change in macrocirculation
Macrocirculation will be assessed using standard ultrasound measurements at the carotid and femoral levels (arteries and veins).
Measured: At baseline, during the 10 days of the intervention, and at 3 days after the end of the intervention
Change in endothelial function
The tests consists in the measurement of the variations of the brachial artery diameter as a response to shear stress.
Measured: At baseline, during the 10 days of the intervention, and 3 days after the end of the intervention
Myofiber atrophy evaluation
Biopsy sampling from m. vastus lateralis will be performed to measure structure and function of muscle fibers.
Measured: At baseline and at day 9 of intervention
Changes in jump performance
Jump performance will be assessed on a platform and height of the jump will be evaluated
Measured: At baseline and 1 day after the end of the intervention
Change in protein metabolism
Labeled tracers (¹³C leucine for oxidation, ¹⁵N-phenylalanine for degradation, ²H₅-phenylalanine for synthesis monitoring and NaH13CO3 for quantification of amin acid oxidation) will be infused to the volunteers, and blood, urine, muscle and breath samples will be collected.
Measured: At baseline and at day 9 of the intervention
Change in muscle strength
Muscle strength will be assessed via dynamometry
Measured: At baseline and 2 days after the end of the intervention
Change in bone biological marker
Measuring bone-specific Alkaline Phosphatase (bAP) in blood
Measured: At baseline, during the ten days of intervention and until 90 days after the end of the intervention
Changes in bone density (by High Resolution Peripheral Computed Tomography (HR-pQCT))
Bone density (g/cm2) is measured at tibia and radius level with HR-pQCT.
Measured: At baseline and until 90 days after the end of the intervention
Changes in Resting Metabolic Rate (RMR)
RMR will be measured by indirect calorimetry technique
Measured: At baseline, during the ten days of intervention and until 90 days after the end of the intervention
Change in nitrogen balance
Nitrogen balance is a measure of nitrogen input minus nitrogen output. Nitrogen intake is calculated with a nutrition software. Protein oxidation measured in the 24-Hour urine collection estimates nitrogen output.
Measured: At baseline, during the ten days of intervention and at 90 days after the end of the intervention
Change in metabolic flexibility (Oral Glucose Tolerance Test (OGTT))
Metabolic flexibility will be measured during OGTT to assess the ability of the body to adjust energy substates' availability.
Measured: At baseline and 4 days after the end of the intervention.
Change in glucose homeostasis
Continuous measurement of interstitial glucose concentration by Dexcom sensor
Measured: From baseline to day 5 after the end of the intervention
Change in energy expenditure of tissues and organs (by PET-scan)
Regional mapping of metabolic activity by dynamic PET-scan with ¹⁸F-fluorodeoxyglucose
Measured: At baseline and at day 7 of the intervention period
Metabolic change in adipose tissue
Histology, cell culture, adipocyte size distribution and whole adipose tissue transcriptome, proteome, lipidome and metabolome on adipose tissue biopsy
Measured: At baseline and at day 9 of the intervention
Change in gut microbiota
Gut microbiome, metabolome and proteome will be measured in stool samples
Measured: At baseline, during the ten days of the intervention and 4 days after the end of the intervention period
Modification of self perceived hunger
Questionnaires about self-perceived hunger will be delivered before and after breakfast, lunch, snack, and dinner, or at the equivalent times on the fasting days. The questionnaire consists of a Visual Analogue Scale on which the volunteer must indicate their level of hunger (from 'not at all' to 'extremely')
Measured: At baseline, during the ten days of the intervention and until 4 days after the end of the intervention period
Change in energy requirements
Change in energy requirements using water labeled with a stable oxygen isotope (H218O)
Measured: At baseline and at day 9 of the intervention period
Change in motor function (Sit-to-stand test)
Sit-to-stand test : volunteer will be requested to rise as fast as possible from a chair without using hands and stand for 10s. The following parameter will be measured : Settling time after standing.
Measured: At baseline and 1 day after the end of the intervention period
Change in standing balance
This test assesses standing balance on a platform covered with 12-cm thick medium density foam.
Measured: At baseline and 1 day after the end of the intervention period
Change in vestibular health
Battery of tests will be used to asses vestibular health: recovery from fall, path integration, distance perception, perception of self-rotation, how long 1', Posner task, antisaccade task
Measured: At baseline and 1 day after the end of the intervention period
Change in cognitive state
This test monitor changes in the subject's emotional state and executive function by evaluatingpsychotechnical tasks on a laptop (the neurosensorybox) with physiological sensors (SOMNO HD system).
Measured: At baseline, during the ten days of the intervention period and at day 5 after the end of the intervention
Salivary cortisol evolution
To characterize stress level, morning and evening salivary cortisol (ng/ml) will be assessed
Measured: At baseline, at day 1, 3 & 10 of intervention period, and day 4 after the end of the intervention
Change in memory performance
Subjects are exposed to a series of images that will have to be remembered. After a delay of 1 hour or 24 hours they will be questioned on a series of images presented under the same conditions and they will have to indicate in a grid whether these images are known or new
Measured: At baseline, during the ten days of the intervention period, and until 3 days after the end of the intervention
Change in the internal representation of 3D space
This tests consist in a rhythmic point-to-point hand movements in virtual reality.
Measured: At baseline, during the ten days of the intervention period, and until 3 days after the end of the intervention
Change in gastro-brain interaction
Assessment of the correlation between gastric electrical activity (measured via Electrogastrography) and neural oscillatory responses (measured via Electroencephalography) during a cognitive task
Measured: At baseline, during the ten days of the intervention period, and until 4 days after the end of the intervention
Change in motor function (Walk and turn test)
Walk and turn test : volunteer will be instructed to walk as quickly as possible straight ahead toward a cone walk around it and return to the chair. Completion time per walk-and-turn trial will be measured.
Measured: At baseline and 1 day after the end of the intervention period
Change in motor function (Tandem Walk)
Tandem walk : Volunteer will walk 10 heel-to-toe steps with their arms folded across their chests and their eyes closed (3 trials) followed by one trial with their eyes open. Percentage of correct steps will be measured.
Measured: At baseline and 1 day after the end of the intervention period
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Mar 2026
- Study start10 Mar 2026
- Primary completion28 Sep 2026 (estimated)
- Study completion28 Sep 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for MicrogravityStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 10 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Centre National d'Etudes Spatiales
- Sponsor type
- Other government
- Collaborators
- MEDES Institut de Médecine et de Physiologie Spatiales, Toulouse
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07499167
- Sponsor's protocol ID
- 25-369
- Acronym
- BRAHMS
- Status last verified
- Jul 2026
- First submitted
- 27 Feb 2026
- Last updated
- 10 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 10 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- BRAHMS: Bed Rest And HypoMetabolism Study Integrative Physiological Responses to 10 Days of Bedrest and Caloric Restriction: An Exploratory Pilot Study In 10 Healthy Men.
- ClinicalTrials.gov ID
- NCT07499167
- Acronym / sponsor ID
- BRAHMS / 25-369
- Conditions
- Microgravity, Caloric Restriction
- Keywords
- Microgravity, Caloric restriction
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 10 participants (estimated)
- Lead sponsor
- Centre National d'Etudes SpatialesOther government
- Collaborators
- MEDES Institut de Médecine et de Physiologie Spatiales, Toulouse
- Study start
- 10 Mar 2026 (actual)
- Primary completion
- 28 Sep 2026 (estimated)
- Study completion
- 28 Sep 2027 (estimated)
- First posted
- 30 Mar 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this single arm, interventional monocentric clinical trial is to investigate the physiological effects of a combination of head-down bedrest and caloric restriction on the human body. A set of measurements will assess the changes in the musculoskeletal, cardiovascular, hematological, immune, neurological, cognitive and metabolic systems, in 10 healthy male volunteers.
The main question it aims to answer is: what are the physiological responses to fasting in a microgravity environment?
In an exploratory study such as this one, where many physiological systems are explored, it is difficult to select a single important endpoint. However, given the known effect of both caloric restriction and head-down bedrest on muscle loss, and its critical importance for the success of space missions, lean body mass, as assessed by DEXA, was chosen as the primary endpoint.
The secondary endpoints are:
- Cardiovascular, muscular, neuro-vestibular and neuropsychological functional performance
- The onset of clinical symptoms and biological changes
Participants will be exposed to a microgravity analog model (head down bed rest) and controled caloric restriction environment for 10 days, multiple physiological assessments will be performed during this period. Followed by a rehab period before leaving the study.
Study design
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Caloric restriction | Experimental | Other: head down bedrest and caloric restrictionhead down bedrest and caloric restriction (250 kcal/day) |
Who may qualify
- Ages
- 20 to 40 years
- Sex
- Male only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (15 listed)
- Healthy male volunteers (see below the description of medical tests and laboratory analysis performed at the selection visit)
- Certified as healthy by a comprehensive clinical assessment (detailed medical history and complete physical examination): in particular, free from any known chronic disease or any acute mood or eating disorder, infectious disease or cardiovascular, metabolic, neurological, ENT (especially orthostatic hypotension and vestibular disorders), orthopedic or musculoskeletal disorders.
- 20 to 40 years old
- 165 to 185 cm
- Body Mass Index between 20 and 26 kg.m-2
Key exclusion criteria (41 listed)
- Any history or presence of clinically relevant chronic disease; any acute infectious disease. Particularly (but not limited to):
- Symptomatic orthostatic hypotension whatever the decrease in blood pressure, or asymptomatic postural hypotension defined by a decrease in SBP equal to or greater than 20 mmHg within 3 minutes when changing from the supine to the standing position
- Personal or family history of thrombosis, genetic mutation for factor V or prothrombin gene
- Cardiac arrhythmia
- Hypertension
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| head down bedrest and caloric restrictionthe intervention is 10 days of head down bedrest (-6°) and controlled and progressive caloric restriction, then controlled and progressive refeeding | Other | Caloric restriction |
Primary outcome
Lean Body Mass
Time frame: At baseline, during the ten days of intervention and until 90 days after the end of the intervention
Lean Body Mass assessed by dual energy x-ray absorptiometry (DEXA)
36 secondary outcomes
Change in body fluid compartments by bioelectrical impedance analysis
Time frame: At baseline, during the ten days of intervention and until 90 days after the end of the intervention
Change in whole-body Magnetic Resonance Imaging (MRI)
Time frame: At baseline and at day 9 of intervention period
Change in mood
Time frame: At baseline, during the ten days of intervention and until 4 days after the end of the intervention
Assessment of movements by volunteers
Time frame: At baseline, during the ten days of the intervention and until 4 days after the end of the intervention
Change in cardiovascular deconditioning and orthostatic tolerance (stand test)
Time frame: At baseline and 1 day after the end of intervention period
Changes in orthostatic tolerance
Time frame: At baseline and 1 day after the end of intervention period
Changes in peak aerobic power (VO2max test)
Time frame: At baseline and 4 days after the end of intervention period
Changes in plasma volume
Time frame: At baseline, during the ten days of the intervention and until 4 days after the end of the intervention
Change in long term blood pressure
Time frame: At baseline, during the 10 days of the intervention, and 4 days after the end of the intervention
Change in macrocirculation
Time frame: At baseline, during the 10 days of the intervention, and at 3 days after the end of the intervention
Change in endothelial function
Time frame: At baseline, during the 10 days of the intervention, and 3 days after the end of the intervention
Myofiber atrophy evaluation
Time frame: At baseline and at day 9 of intervention
Changes in jump performance
Time frame: At baseline and 1 day after the end of the intervention
Change in protein metabolism
Time frame: At baseline and at day 9 of the intervention
Change in muscle strength
Time frame: At baseline and 2 days after the end of the intervention
Change in bone biological marker
Time frame: At baseline, during the ten days of intervention and until 90 days after the end of the intervention
Changes in bone density (by High Resolution Peripheral Computed Tomography (HR-pQCT))
Time frame: At baseline and until 90 days after the end of the intervention
Changes in Resting Metabolic Rate (RMR)
Time frame: At baseline, during the ten days of intervention and until 90 days after the end of the intervention
Change in nitrogen balance
Time frame: At baseline, during the ten days of intervention and at 90 days after the end of the intervention
Change in metabolic flexibility (Oral Glucose Tolerance Test (OGTT))
Time frame: At baseline and 4 days after the end of the intervention.
Change in glucose homeostasis
Time frame: From baseline to day 5 after the end of the intervention
Change in energy expenditure of tissues and organs (by PET-scan)
Time frame: At baseline and at day 7 of the intervention period
Metabolic change in adipose tissue
Time frame: At baseline and at day 9 of the intervention
Change in gut microbiota
Time frame: At baseline, during the ten days of the intervention and 4 days after the end of the intervention period
Modification of self perceived hunger
Time frame: At baseline, during the ten days of the intervention and until 4 days after the end of the intervention period
Change in energy requirements
Time frame: At baseline and at day 9 of the intervention period
Change in motor function (Sit-to-stand test)
Time frame: At baseline and 1 day after the end of the intervention period
Change in standing balance
Time frame: At baseline and 1 day after the end of the intervention period
Change in vestibular health
Time frame: At baseline and 1 day after the end of the intervention period
Change in cognitive state
Time frame: At baseline, during the ten days of the intervention period and at day 5 after the end of the intervention
Salivary cortisol evolution
Time frame: At baseline, at day 1, 3 & 10 of intervention period, and day 4 after the end of the intervention
Change in memory performance
Time frame: At baseline, during the ten days of the intervention period, and until 3 days after the end of the intervention
Change in the internal representation of 3D space
Time frame: At baseline, during the ten days of the intervention period, and until 3 days after the end of the intervention
Change in gastro-brain interaction
Time frame: At baseline, during the ten days of the intervention period, and until 4 days after the end of the intervention
Change in motor function (Walk and turn test)
Time frame: At baseline and 1 day after the end of the intervention period
Change in motor function (Tandem Walk)
Time frame: At baseline and 1 day after the end of the intervention period
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 10 Jul 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing head down bedrest and caloric restriction in people with Microgravity and Caloric Restriction, run by Centre National d'Etudes Spatiales at 1 site in France.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 15 inclusion and 41 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 10 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in France. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Lean Body Mass (time frame: At baseline, during the ten days of intervention and until 90 days after the end of the intervention). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 10 Jul 2026.